Eye tracking is a widely used research method, but there are many questions and misconceptions about how to effectively apply it. Eye Tracking the User Experience—the first how-to book about eye tracking for UX practitioners—offers step-by-step advice on how to plan, prepare, and conduct eye tracking studies; how to analyze and interpret eye movement data; and how to successfully communicate eye tracking findings.

Finally, a useful and usable book about what eye tracking really is—and isn’t—for user experience practitioners. Bojko uses plain language and clear, concrete examples (many of which you will borrow!) to explain the realities and dispel the myths of how eye tracking fits and adds value in a mature user-experience research program.

Do I need eye tracking in my research?
It’s like asking “Do I need a microscope?” You don’t need one to see the dust bunnies under your bed, but you do if you want to find a dust mite. It all depends on what you are looking for. So maybe you do need eye tracking, maybe you don’t.Let Chapter 2 be the judge.

Eye tracking is not useful. I’ve seen heatmaps, and they didn’t tell me much.
First, this is not a question. Second, eye tracking is so much more than heatmaps. (As described in Chapter 11, those should only be used in a supplemental role.) Third, whoever gave you heatmaps in place of actual data analysis needs to read this book. Cover to cover. I will gladly hold on to their eye tracker until they are done.

How many participants should I get for an eye tracking study?
42.Just kidding. As much as you’d like a simple answer, there isn’t one. If you are ready for the truth about sample size and all the factors that it depends on, make yourself a sandwich and proceed to Chapter 8.

Which eye tracking measures should I use?
None, if your study is purely formative, and you are just looking for usability issues. But if you are conducting summative research, you should choose your measures based on the cognitive processes you’re trying to assess. There is no one measure that is perfect for every study, not even my favorite—average fixation duration.Chapter 7 will gently guide you in your measure selection process.

How do I analyze the data?
Brownie points for asking the question! Yes, data need to be analyzed before they can provide useful information. You don’t just generate some heatmaps or scanpaths and call it a day. First, you carefully prepare your data for analysis. (Data cleansing is key.) Then, depending on the type of analysis—qualitative or quantitative—you systematically inspect visualizations or calculate statistics.For step-by-step instructions, refer to Chapters 10 through 13.

Why do you keep saying that eye tracking is “just not that special?”
Because as a method, it really isn’t. An eye tracking study should be subject to the same research principles as any non-eye tracking UX study. There are, of course, a few additional considerations, but the core is always the solid and well-established scientific method. Once everyone realizes that, eye tracking will become a more rigorous and systematic undertaking in the UX field than it may have been thus far. And that’s the goal of this book.

Excerpts

Foreword

Eye tracking has always seemed very promising. After all, in our profession we spend a lot of our time trying to read users’ minds. One of our most powerful tools—usability testing—consists simply of asking users to think aloud while they use our products so that we can understand where they’re getting confused. I describe it as trying to see the thought balloons forming over users’ heads, especially the balloons that have question marks in them. They’re the ones that tell us what needs fixing.

Eye tracking is naturally appealing to us because it holds out the promise of another window into the mind: the semi-magical ability to know what people are looking at. And since there seems to be a strong (though not absolute) connection between what people are looking at and what they’re paying attention to, eye tracking can provide another set of useful clues about what they’re thinking and why the product is confusing them.

At the very least, it promises to answer questions like “Did they even see that big button that says ‘Download?'” If the eye tracking shows that people aren’t seeing it, then we know that they can’t possibly act on it, and we should probably give some thought to making it more prominent somehow.

That’s why eye tracking is one of the three technologies I’ve been waiting for, for a long time.1 In fact, when I wrote Don’t Make Me Think, it was going to be based in part on some eye tracking research I was going to do. But it turned out that the technology at the time—particularly the software to analyze the mountains of data that eye trackers produce—just wasn’t up to the task. Fifteen years ago eye trackers were for specialists who spent all their time feeding them their specially prepared fuel pellets, writing their own analysis software, and trying to read the resulting runes.

Then came the millennium and a quantum leap forward by the manufacturers. All of a sudden, instead of requiring programming skills, bailing wire, and a soldering iron, eye trackers worked right out of the box. And they came with software that let almost anyone—anyone with $30,000—generate impressive output, especially (God help us!) heat maps.

Over the years, I’ve sat through countless demos and presentations, and tried to read everything that was written about eye tracking and UX. At one point, one of the manufacturers was even nice enough to give me a loaner for a few months, so I had the chance to do a little experimenting myself. The upshot is that I’ve always known a lot about eye tracking for someone who doesn’t actually do eye tracking.

And here’s what I know:

Eye tracking is sexy. Harry Brignull once did a presentation that drew an analogy between eye trackers and the shoe-fitting fluoroscopes that were used in shoe stores from the 1920s to the 1960s.2 Your child would put his or her feet in an opening at the bottom of the machine, and you could peer in and see the bones inside, giving you the comforting knowledge that the shoes weren’t going to warp your child’s tender feet. It was fascinating, it was science (not opinion), and it offered the promise of proof. And it had lots of sizzle.3 Heatmaps have the same kind of sizzle.

It sells. Even though we can all agree in retrospect that the shoe-fitting fluoroscope was probably not a good idea, it sold shoes. And blinding people with science still works: eye trackers sell UX services. You can probably charge more if your deliverables include some heatmaps, whether they show anything that’s useful or not.

It seems easy. But it’s not. It’s no trick nowadays to do some eye tracking and create compelling graphics that make it seem like you’re proving something. But actually knowing what you’re doing takes time, experience, and learning.

It’s hard to learn how to do it well. There have been tons of academic papers and manufacturers’ white papers, but no one has produced a how-to book for practitioners.

Enter Aga.

Actually, I’d like to take a tiny bit of credit for this part. I’d heard Aga speak several times over the years, so I knew that she always had the smartest things to say about eye tracking and UX. Then I read an article she wrote for the UX magazine and discovered that she was a really, really good writer. So I told Lou Rosenfeld he needed to get her to do a how-to book. Now that it’s here, I feel a little like a proud uncle. Or maybe a matchmaker.

Believe me, you’re in good hands. Aga really knows her stuff, and she’ll tell you just what you need to know. This is, as she’s described it, “The book I wish I’d had when I was starting out doing eye tracking.” What more can you ask for?

BTW, if I were an eye tracking manufacturer, I’d buy a few hundred copies and give them away to all my customers and potential customers. And then I’d loan Steve Krug another eye tracker.

—Steve Krug
Author of Don’t Make Me Think

1. The other two are consumer-affordable speech recognition good enough to do accurate dictation (finally happened in the late 1990’s) and reliable lie detection (still “twenty years off”). Curiously, I don’t know of anyone other than me who thinks that effective lie detection would cause greater social disruption than, say, an infinite source of free, clean energy, or anti-gravity boots.↩2. Harry Brignull’s presentation slides can be found at http://j.mp/eye-tracking-uxlx.↩3. Probably not literally. No one has tracked down whether anyone suffered ill effects from the radiation.↩

Acknowledgments

The path that led me to this book started with my parents. They always encouraged my interests in behavioral sciences, learning foreign languages, writing, and teaching—all important ingredients of this book. Mamo i tato: Jestescie najlepszymi rodzicami jakich mo˙zna sobie wymarzyc.

Next, it was Paula Goolkasian, a University of North Carolina professor, who took a chance on a Polish exchange student and gave her research and publication opportunities that later opened many doors. That’s when my fascination with visual perception began. Dr Goolkasian, I can’t thank you enough.

In 2003, I met Bob Schumacher and Gavin Lew, who took me on an amazing journey packed with countless research adventures, crazy but brilliant ideas, exciting challenges, and, of course, eye tracking. This book wouldn’t exist without their unwavering support and Bob’s occasional nagging. Guys, it is an absolute privilege to have you as my mentors and friends.

In 2010, I got an email from Lou Rosenfeld, the publisher of this book. It turned out that Steve Krug sent him one of my eye tracking articles and suggested that I should write a book. Lou, thank you for listening to Steve. Steve, you rock.

As you can imagine, a lot of people were involved in the making of this book. First and foremost, I’d like to thank the Rosenfeld Media team for all their work getting the book into its print and digital forms. Special thanks go to Lou and my editor, Marta Justak, for their invaluable guidance and for never giving up on me, even though my interpretation of the word “deadline” might have been a little unconventional at times.

I’m indebted to Kristin Adamczyk and Patrick Squire for their many contributions to this book and for all the eye tracking studies we have done together over the years. I can sleep at night because I know I can always count on you.

I’d also like to acknowledge those who helped out with answers to questions, obtaining permissions, and creating visuals for the book: Naghmeh Shafiei, Tommy Strandvall, Mark Mento, Julie Murphy, Patrick Fleming, Ashley Smith, Gaye Walker, Suzanne Foy, Virginia Salem, and the many, many amazing people from the User Centric team.

And last but not least, a huge thanks to my family and friends for cheering for me so patiently for the last couple of years (and for fondly comparing the length of this process to the gestation period of an elephant). I’m back.

Testimonials

If you are like me, you are a secret tools geek and get a little eye tracker envy every time you wander through a particularly well-equipped lab. Eye Tracking the User Experience is an excellent manual on how to leverage eye tracking for a deeper understanding of how people are responding to your designs. It covers virtually every facet of what you need to know to incorporate eye tracking into your methods toolkit, and is rich with practical advice and examples from Aga Bojko’s experience.

Arnie Lund, author of User Experience Management

Sometimes skeptical, sometimes enthusiastic, but always full of insight: Aga Bojko’s thorough and readable discussion of eye tracking will help you to make informed choices about whether to use it on your project, and about how to get actionable insights from it.

Caroline Jarrett, user experience consultant and author of Forms that Work

Through case studies and quantitative and qualitative methods, Eye Tracking the User Experienceoffers practical advice and plenty of examples, and makes the case for when eye tracking is and isn’t appropriate.

Jeff Sauro, author of Quantifying the User Experience: Practical Statistics for User Research

Eye Tracking the User Experience is one of the most approachable eye tracking books I have had the pleasure of reading. The book is richly illustrated and clearly written, giving the rationale and means for easily adding eye tracking to the UX practitioner’s arsenal. The book provides practical guidance from deciding on the right equipment to finding the right study setting, from establishing test questions and tasks to estimating the number of participants, from running the study to data extraction and analysis. Case studies are given throughout, showing how eye tracking proffers actionable insights to the study of user experience.

Finally, a useful and usable book about what eye tracking really is—and isn’t—for user experience practitioners. Bojko uses plain language and clear, concrete examples (many of which you will borrow!) to explain the realities and dispel the myths of how eye tracking fits and adds value in a mature user-experience research program.